\end{haskelllisting}
A bar consists of a time signature and a list of chord symbols. Bars have the following
input syntax:
\begin{verbatim}
bar = { chord | timeSig | '%' | '_' }
timeSig = '(' int '/' int ')'
\end{verbatim}
If no time signature is provided then a default is used (within chord chart the time
signature of the bar before, and 4/4 for the first bar). The character '\%' is a short-cut
for the chords just before. The character '\_' denotes a break.
\begin{haskelllisting}